1. Technical Field
The present disclosure relates to a method, an apparatus and a system to manufacture an actuation sled and, more particularly, to a mold for injection molding of an actuation sled.
2. Background of Related Art
Injection molding is a manufacturing process for producing parts and components. This process typically consists of inserting a molding material into an open rigid mold. The mold may be formed by halves. Typically, injection molding incorporates stationary and ejector mold halves, which open and close, to define a cavity where the molding or casting material is injected. Stationary mold halves are generally mounted to stationary platens. Ejector mold halves, in contrast, are capable of moving relative to stationary holder blocks for opening and closing the cavity. Ejector mold halves are mounted to ejector platens, which are generally connected to hydraulic actuators for providing movement. The stationary mold and the ejector mold are generally clamped together before the molding material has been injected into the cavity. After a suitable curing cycle, the mold is separated from the formed product. A successful injection molding process produces a part or a product substantially shaped as the mold.
The injection molding process, however, does not necessarily produce flawless products. The quality of the manufactured product is occasionally compromised by shortcomings during the injection molding process. For instance, gas within the molding cavity can substantially diminish the quality of the final product. Vacuum assistance has been used to address this issue and improve product quality. The general purpose of the vacuum assistance is to improve the production of injection molding by removing gases from within the molding cavities. Ideally, vacuum assisted injection molding produces parts with a reduced level of porosity and greater physical characteristics.
The physical characteristics of a molded article can also be improved by positioning vents on the molds. These vents release gases that otherwise would be trapped within the mold cavity. Consequently, vents reduce the occurrence of defective articles by minimizing incomplete mold cavity fillings. However, gases within the molding cavity are not the only cause of low quality products during the injection molding process. Occasionally, molding material is not uniformly distributed within the mold cavity. Thus, there is a need for a method, system, and apparatus for evenly distributing molding material throughout the mold cavity during an injection molding process.
Medical devices manufacturers often employ injection molding to produce certain components of surgical instruments. For example, some parts of surgical staplers are manufactured using injection molding. In particular, actuation sleds can be made by injecting molding material into a mold cavity. Actuation sleds serve to drive staple pushers vertically and, thus, eject staples. Actuation sleds typically include spaced apart ramps or cam wedges. These cam wedges are designed to cooperate with angular surfaces of the staple pushers to eject the staples. The angular surface of the staple pushers and the cam wedges complement each other. The cooperation between the angular surfaces of staple pushers and the actuation sled is a key step of the surgical stapling process. Hence, actuation sleds should have cam wedges with the least amount of imperfections. It is thus desirable to develop an apparatus, system, and method to manufacture high quality actuation sleds.